HRAA
stands for High Resolution Anti-Aliasing. The HRAA technology was
introduced first by the late 3DFX with the Voodoo 5500: over the past two
years this technology took an important place. The purpose of HRAA is to
remove aliasing effects like popping pixels or scaled shapes to make the
3D scene more realistic.

With
the release of the GeForce 2, NVIDIA introduced a basic but efficient
anti-aliasing method called supersampling that used different 2x or 4x
levels (using a 2 or 4 times higher resolution). It works like this: when
supersampling is enabled the GPU internally rendered the scene in a higher
resolution than the one it should be displayed in, and then lowered the
resolution by applying a filter before the scene can be finally displayed.
The major drawback of this technology was the fact it really slows down
the whole graphic display resulting in a poor FPS rate. NVIDIA’s answer
to this problem is the new QuinCunx extension brought by the GeForce 3.
Their new technique is supposed to give the visual result of a 4x anti-aliasing
with the speed of a 2x one. To do so, QuinCunx (no, this is not slang!)
interpolates pixels more efficiently than before: instead of using only
two points of the scene to interpolate colors, it now combines adjacent
pixels.

Below
are the official performance rates announced by NVIDIA when using QuinCunx
with Quake III Arena:

Reading
these numbers, you’ll instantly notice that the GeForce 3 is 50% faster
than its predecessor even with a weaker fillrate. It proves the undeniable
efficiency of the Light Speed Memory Architecture.

Since
the GeForce 3 supports multi-sampling, it can perform all the DirectX 8.0
effects like the Motion Blur or the Depth of field. Notice that
reflections effects are more realistic than ever when using the
Soft-Reflections or Soft-Shadows especially when an object is reflected on
a defined material. Contrary to the new features introduced by the nFinite
FX engine, actual games can take advantage of the HRAA technology right
now and don’t need to be adapted.

Transform &
Lighting

As
surprising as it can be, the Transform & Lighting engine actively
promoted by NVIDIA is now nearly dead! If its successor called nFinite FX,
is more than worth of that name, the GeForce 3 still includes a less
elaborated transform and lighting engine than in previous generations to
ensure compatibility with games
designed for Direct X 7.0 and other ones like Quake
III
(the hardwired T&Lalso saves execution time if
a game doesn't require the services of the
Vertex Shader).

nFinite FX

The
supreme new feature of the GeForce 3 is the brand new redesigned graphic
engine called, in all modesty, nFinite FX. This new engine combines two
modules in one: the Pixel Shaders and the Vertex Shaders in order to take
full advantage of the latest DirectX 8.0 set of instructions. First
you have to know what is a Vertex: a
vertex is the corner of the triangle where two edges meet, and thus every
triangle is composed of three vertices. A vertex
usually carries several information, like its coordinates, weight, normal,
color, texture coordinates, fog and point size data. A Shader is a small
program that executes mathematical operations to
alter data so a new vertex emerges with a different color, different
textures, or a different position in space. Vertex Shaders are run by the
GPU (so it doesn't consume CPU horsepower) to act on triangles’ top
(vertices: it concerns every polygon shape) associated data for the Vertex
Shaders or on the pixels for the Pixels Shaders. Now
let's see the Pixel Shaders. If every 3D scene is composed of pixels
generated by Pixels shaders, the Geforce 3 comes with 4 Pixel Shaders
aimed to convert a set of texture coordinates (s, t, r, q) into a color (ARGB),
using a shader program. Pixel shaders use floating point math, texture
lookups and results of previous pixel shaders. A pixel shader can execute
programmed texture address operations on up to four textures and then run
eight freely programmed instructions of texture blending operations that
combine the pixel's color information with the data derived from the up to
four different textures. Then a combiner adds specular lighting & fog
effects to make the pixel alpha-blended, defining its opacity. In
comparison to GeForce 2 NSR, the GeForce 3 pixel shaders are definitely
more advanced. They fetch two texels per clock cycle, allowing up to four
textures per pass. When a game attempts to apply more than two textures
per pixel, the Geforce’s pixel shader require 2 clock cycles for three
or four textures but still perform this in only one pass against several
for the GeForce 2. Finally Geforce 3 pixel shaders save valuable memory
bandwidth: indeed when you attempt to render 3 or 4 textures per pixel the
GeForce 3 requires only 1600MB/s while the GeForce 2 would consume
3200MB/s.Those
pixel shaders are essential to bring movie-style game to your PC since
they process a huge load of data. Until now no graphic processor was able
to render such effects in real-time.
With 27 new
instructions for the Vertex shader, and 23 new instructions for the Pixels
shader, games’ developers are freer than ever to express their
creativity, realizing the craziest things their imagination suggests. In
other words, the vertex shaders inject personality into characters and
environments while the pixel shaders create ambiance with materials and
surfaces that mimic reality.With
such a technology, developers not only use pre-cabled instructions from
NVIDIA but they also create and upload their own algorithms into the GPU
bringing to life brand new graphic effects engine! Due
to its flexibility, listing the effects that can be managed by the GeForce
3 is simply impossible, but here are some of the most famous things that
are now supported: enhanced Matrix Palette Skinning, Keyframe Animation
(used by 3D morphing), 3D objects can be distorted to simulate waves,
wind, etc. The only limit developer will face is that a vertex shader can’t
exceed 128 instructions.

Both
of these modules open the door for highly realistic games that will
definitely take your breath away, taking the visual experience to a new
level especially when combined to the Environmental Bump Mapping.
Remember! When Matrox introduced its G400 series of graphic card, a brand
new and unique 3D feature called Environmental Bump Mapping also appeared.
The GeForce 3 at last includes this technology to simulate relief in 3D
scenes by playing with light effects. The Environmental Bump Mapping
process is actually the most realistic technology as shown by one of the
3D Mark 2001 scenes. Games optimized for the GeForce 3 GPU will feature
more fluid and more accurate graphics, with an unprecedented level of
details, thanks to the technologies explained above.

Above
are shots from nVidia technological demos & games that are optimized
for the GeForce 3 (click to enlarge)

Higher Order
Surfaces

Behind
this name lies a new technology designed to save AGP bus bandwidth.
According to NVIDIA, AGP can limit the performance of its new GPU. They
submitted the following example to highlight this potential problem: a
scene that contains 100,000 triangles, each one composed of 3 vertices
weighing approximately 50 bytes. It makes 14.3 MB of geometric information
per image, so at 60 frames per seconds the whole scene weighs 858 MB that
should pass through the AGP port. The problem is that the 4x AGP port can
actually offer only, in best cases, a 1 GB/s transfer rate (Roll on AGP
8x!) so games can quickly become limited (even if actually few games use
as many triangles!) in a few months. The workaround NVIDIA used to fix
this potential problem comes once again from Microsoft and its Direct X
8.0 set of API (application programming interface). The GeForce 3 now
supports the High Order Surfaces feature introduced by Direct X 8.0. HOS
replaces heavy to transfer triangles by surfaces composed of different
control points that are primarily much faster to transfer while being at
the same time totally flexible thanks to mathematical functions. Using
this function surfaces are now composed of curves saving part of the AGP
bandwidth instead of engorging it with triangles. The advantage is
obvious: drawing a simple sphere requires thousands of traditional
triangles to be drawn while only 4 rectangular patches (and some
functions) are needed when using HOS. Once this information is sent to the
GeForce 3, it’s time for the GPU to achieve the tessellation to
transform HOS into a more or less important number of polygons depending
on the requested detail level. To enjoy this feature, games should
obviously come with a redesigned 3D engine that supports it, which is not
the case of most games today. Thus games’ developers will have to choose
between the two HOS functions supported by Direct X 8.0: N-Patches or RT-Patches
(rectangular/triangular), if RT-Patches are suppler and give a better
lookout, N-Patches are more easy to use :).HOS
paves the way for faster and more realistic games until AGP 8x arrives.